1. Field of the Invention
The present invention relates to a projection apparatus, and more particularly, to a projection apparatus capable of quickly adjusting a position of an image projected thereby.
2. Description of Related Art
With the rapid advance in technologies, various types of projection apparatus are deployed in many different occasions such as briefings, lectures, theatres, audio-visual lecturing, activity teaching and home theatre. To meet the requirements of users, the projection apparatus has a light and compact design and a projection angle of the projection apparatus is adjusted through a supporting leg.
FIG. 1A is a top view of a conventional projection apparatus, and FIG. 1B is a front view of the projection apparatus in FIG. 1A. As shown in FIGS. 1A and 1B, the projection apparatus 100 includes a casing 110, a projection lens 120, two elevating legs 130 and a supporting leg 140. The casing 110 has a front end 112, a rear end 114 and a bottom portion 116. The projection lens 120 is assembled to the front end 112 of the casing 110. The two elevating legs 130 are disposed separately on the bottom portion 116 of the casing 110 close to the front end 112 and the supporting leg 140 is disposed on the bottom portion 116 of the casing 110 close to the center of the rear end. As shown in FIG. 1C, users are free to independently adjust the two elevating legs 130 when using the projection apparatus 100 so that the degree of elevation (α) and the degree of inclination (β) of the projection apparatus 100 are changed to adjust the position of the projected image. In general, the elevating legs 130 of a conventional projection apparatus 100 are made up of elevating screws. To perform an adjustment, the projection apparatus 100 has to be lifted up before adjustment being made, which is difficult and inconvenient for users. Therefore, some of the manufacturers have made some improvements to the mechanism of the elevating legs to resolve this problem, for example, in U.S. Pat. No. 6,302,543 B1. However, the solution recited in U.S. Pat. No. 6,302,543 B1 has a rather complicated mechanism and the cost of production is relatively high.